Gene Therapy, Stress and Hippocampal Function

描述（由申请人提供）：研究了海马的突触可塑性、在认知中的作用以及在成年海马中发生的神经发生。随之而来的是对海马功能的内分泌调节剂的认识。具体来说，糖皮质激素（GC），在应激期间分泌的肾上腺类固醇，破坏[或]损害突触可塑性和认知的方面，并抑制神经发生。相反，雌激素增强可塑性、认知和神经发生。在使用病毒载体将转基因递送到CNS中方面也取得了进展。我们将在基因治疗策略中使用单纯疱疹病毒1型载体来保护海马免受GC和压力的破坏性影响，并将其中一些GC效应转化为有益的雌激素效应。我们已经构建并希望探索载体的保护潜力，所述载体表达a）降解GC的酶; B）显性负性GC受体; c）结合GC但具有雌激素受体的基因组作用的嵌合类固醇受体。在目标1中，我们将改变这些载体，使它们能够被应激和GC诱导，作为一种手段，使它们的表达被损伤触发。然后，我们将描述它们的表达模式。然后，我们将检查这些载体的保护潜力，检查前两个备用神经元是否受到GC的不良影响，以及嵌合载体在暴露于GC时是否也产生有益的雌激素效应。在目标2中，终点将是在海马切片中产生的长时程增强，所述海马切片由具有不同的GC暴露或应激的死前方案的大鼠产生。在目标3中，我们将研究GCs，压力和这些载体对依赖于营地的认知任务的影响。在目标4中，我们将研究体外和成年海马中的神经发生。我们将描述GC、应激和雌激素对其的影响，然后确定这些载体是否可以保护神经发生免受GC的抑制作用，并在嵌合载体的情况下，利用这一点产生刺激性雌激素效应。

DESCRIPTION (provided by applicant): The hippocampus has been studied for its synaptic plasticity, role in cognition, and the neurogenesis that occurs in the adult hippocampus. With this has come an appreciation of endocrine modulators of hippocampal function. Specifically, glucocorticoids (GCs), adrenal steroids secreted during stress, disrupt [or] impair facets of synaptic plasticity and cognition, and inhibit neurogenesis. Estrogen, in contrast, enhances plasticity, cognition and neurogenesis. There has also been progress in the use of viral vectors to deliver transgenes into the CNS. We will use herpes simplex virus-1 vectors in a gene therapy strategy to protect the hippocampus from the disruptive effects of GCs and of stress, and to divert some of those GC effects into salutary estrogenic ones. We have constructed and wish to explore the protective potential of vectors expressing a) an enzyme which degrades GCs; b) a dominant negative GC receptor; c) a chimeric steroid receptor which binds GCs but has the genomic actions of an estrogen receptor. In Aim 1, we will alter these vectors to make them inducible by stress and GCs, as a means to have their expression triggered by insults. We will then characterize their patterns of expression. We will then examine the protective potential of these vectors, examining if the first two spare neurons from adverse GC effects, and if the chimeric vector also generates the salutary estrogenic effects when exposed to GCs. In Aim 2, the endpoint will be long-term potentiation in hippocampal slices generated from rats with differing pre-mortem regimes of GC exposure or stress. In Aim 3, we will study the effects of GCs, stress, and these vectors upon a hippocampal-dependent cognitive task. In Aim 4, we will study neurogenesis in vitro and in the adult hippocampus. We will characterize the effects of GCs, stress and estrogen upon it. We will then determine whether these vectors can protect neurogenesis from the inhibitory effects of GCs and, in the case of the chimeric vector, harness this to produce stimulatory estrogenic effects.